problems with code names

[hlageek]

Two problems regarding code names:

1. It seems that we allow for codes with identical names even though some checks for this should be in place
2. We allow for empty code names (again, this means that the checks have a leak somewhere)

[martin-hajek]

This happened when 15+ users were logged in as "Demouser" at the same time and the application was lagging. I think it is a security issue (like buffer overflow) rather than practical one.